1. Field of the Invention
The invention relates to threading arrangements for chainstitch sewing on a sewing machine.
2. Description of the Prior Art
It is well known, that when a sewing machine is to be used for chainstitching, less needle thread must be supplied to the needle than for lockstitching, and that if the amount of thread supplied to the needle is not reduced, improper stitches will be formed. It has been a common practice to provide machines with a special thread guide between a lower positioned thread hook guide and a thread take-up lever, which guide, if used during chainstitching, effected the required reduction in thread supplied to the needle. Such special thread guides required a machine to be threaded one way for chainstitching and another way for lockstitching. However, it was easy for an operator by mistake to thread a machine for lockstitching when it should have been threaded for chainstitching, and when switching from a chainstitching mode to a lockstitching mode to leave a machine threaded for chainstitching. In either event, faulty stitches were produced.
It is a primary object of the present invention to enable a sewing machine to be threaded in the same manner with needle thread for chainstitching and lockstitching.
It is another object of the invention to provide a sewing machine with an easily attachable and detachable chainstitching thread guide which enables the machine to be threaded in the same manner with needle thread whether the guide is in use on the machine or detached from it.
Other objects and advantages of the invention will become apparent hereinafter.